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Thiosemicarbazones are promising classes of compounds with antitumor activity. For this study, six 2,4-dihydroxy-benzylidene-thiosemicarbazones compounds were synthesized. These compounds were submitted to different assays in silico, in vitro and in vivo to evaluate the toxicological, antioxidant and antitumor effects. The in silico results were evaluated by the SwissADME and pkCSM platforms and showed that all compounds had good oral bioavailability profiles. The in vitro and in vivo toxicity assays showed that the compounds showed low cytotoxicity against different normal cells and did not promote hemolytic effects. The single dose acute toxicity test (2000 mg/kg) showed that none of the compounds were toxic to mice. In in vitro antioxidant activity assays, the compounds showed moderate to low activity, with PB17 standing out for the ABTS radical capture assay. The in vivo antioxidant activity highlighted the compounds 1, 6 and 8 that promoted a significant increase in the concentration of liver antioxidant enzymes. Finally, all compounds showed promising antitumor activity against different cell lines, especially MCF-7 and DU145 lines, in addition, they inhibited the growth of sarcoma 180 at concentrations lower than 50 mg/kg. These results showed that the evaluated compounds can be considered as potential antitumor agents.
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Antineoplásicos , Antioxidantes , Tiossemicarbazonas , Animais , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/química , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Camundongos , Humanos , Masculino , Linhagem Celular Tumoral , Simulação por Computador , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Compostos de Benzilideno/farmacologia , Compostos de Benzilideno/químicaRESUMO
A 63-year-old woman presented with dyspepsia de novo. An esophagogastroduodenoscopy revealed a 30 mm flat yellowish esophageal lesion, 28 cm from the incisors (Fig. 1a), with the stomach and duodenum without any lesion. Helicobacter pylori infection was excluded. Histological examination was suggestive of a lymphoproliferative process (Fig. 1b). Immunohistochemistry showed diffuse positivity for CD20 (Fig. 1c) and BCL-2 (Fig. 1d), dim CD10 and BCL-6 staining, a Ki-67 of 20-25%, no CD21 or cyclin D1 expression, all these features compatible with low-grade follicular lymphoma. Physical examination was unremarkable. Computed tomography of the neck, chest, and abdomen revealed no lymph node enlargement, hepatosplenomegaly or metastasis. Blood routine tests and tumor markers were at normal levels. Bone marrow biopsy showed no involvement by lymphoma. Therefore, a diagnosis of primary follicular lymphoma of the esophagus was made. The patient opted for a watch-and-wait strategy and there is no evidence of disease progression after four years of follow-up.
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Infecções por Helicobacter , Helicobacter pylori , Linfoma Folicular , Linfoma não Hodgkin , Feminino , Humanos , Pessoa de Meia-Idade , Linfoma Folicular/diagnóstico por imagem , Linfoma Folicular/patologia , Biomarcadores TumoraisRESUMO
Background: Motion sickness (kinetosis) is a common and temporarily incapacitant ailment, manageable with behavioral as well as pharmacological measures. Objective: To assess the effectiveness and safety of a combination of gamma-aminobutyric acid, glutamic acid, calcium, thiamine, pyridoxine, and cyanocobalamin (Group A) (nâ¯=â¯170) and extract of Zingiber officinale (ginger) (Group B) (nâ¯=â¯165) in the management of chronic complaints consistent with motion sickness. Methods: Both groups were tested according to the following end points, under self-paired as well as comparative study designs: reduction of ≥20 score points in the total motion sickness assessment questionnaire (MSAQ) score, percentage of patients presenting a reduction of the total MSAQ score, absolute MSAQ score reduction, physician's assessment scores, final overall assessment of study medication, and willingness to continue treatment. Safety was also evaluated. Results: There was a statistically significant better performance under both study designs for Group A (Pâ¯=â¯0.05 using different statistical tests) in all end points. Both regimens were safe, with different neurological and gastrointestinal tolerability outcomes. Conclusions: Group A and Group B regimens were effective and safe in the management of chronic complaints consistent with motion sickness and the Group A regimen was more effective than Group B.
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Here we report a case of a relatively rare parasite found upon terminal ileoscopy, in a woman complaining of abdominal pain and living in a developed country.
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Copaiba oil is a natural product used by Amazonian populations and recognized for its medicinal properties because it has significant antimicrobial activity for several pathogenic microorganisms. The present work aimed to evaluate and characterize the effect of natural oil produced by copaiba - Copaifera multijuga against multiresistant isolates of bubaline mastitis. The nitrocefin test was performed with isolates of Staphylococcus aureus from bubaline mastitis, which were 100% positive for beta-lactamase enzyme detection. Minimum Bactericidal Concentration (MBC) of 25% to 3.12% was obtained for Enterococcus faecalis and Escherichia coli and 50% and 25% for S. aureus, but Klebsiella pneumoniae and Bacillus subtilis were resistant. MBC with 12.5% and 6.25% oil were obtained for most multiresistant bubaline mastitis isolates from the states of Pernambuco, Ceará, Bahia and Alagoas. The results demonstrated the great potential of using copaiba natural oil in the treatment of buffalo mastitis.
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Anti-Infecciosos , Fabaceae , Mastite , Brasil , Feminino , Humanos , Mastite/tratamento farmacológico , Mastite/veterinária , Testes de Sensibilidade Microbiana , Staphylococcus aureusRESUMO
BACKGROUND: Motion sickness can be triggered in a variety of situations and is characterized primarily by nausea and vomiting. Ginger is widely used in treating conditions including chemotherapy-associated gastrointestinal symptoms, morning sickness, postoperative nausea, and motion sickness. OBJECTIVES: The primary study objective was to evaluate Zingiber officinale extract in the treatment of motion sickness. Secondary objectives were to evaluate treatment effect on Motion Sickness Assessment Questionnaire (MSAQ) score and subscores before and after treatment, and to evaluate treatment tolerability. METHODS: Open-label, single-arm study assessing motion sickness outcomes with and without pre-travel oral treatment with Zingiber officinale 160 mg extract (containing 8 mg gingerols). All patients answered the MSAQ on 4 separate occasions following a trip of at least 15 minutes in duration: Trip 1 (pretreatment) and Trips 2, 3, and 4 (after oral treatment with study medication). The primary end point was percentage of patients presenting improvement ≥20 score points on the MSAQ during Trip 2, Trip 3, and Trip 4 in comparison to pretreatment score (Trip 1). Secondary end points included percentage of patients presenting improvement in MSAQ subscores during Trips 2, 3, and 4; percentage of patients presenting treatment-related adverse events; and pre- and posttreatment physician assessment scores. RESULTS: One hundred eighty-four patients were included and 174 completed treatment. A reduction of ≥20 points in total MSAQ score points occurred in 26.52%, 29.89%, and 29.31% of patients from Trips 2, 3, and 4, respectively. There was no significant difference at Trips 2, 3, and 4 in number of patients presenting improvement ≥20 score points (Pâ¯=â¯0.9579). There was a significant reduction in total MSAQ scores from Trips 2, 3, and 4 (P < 0.0001) compared with Trip 1. Total MSAQ scores did not vary at each trip taken under treatment (Pâ¯=â¯0.28). There were significant (P < .001) improvements in all domain subscores from Trips 2, 3, and 4 in relation to scores from Trip 1. There was a significant improvement in physician assessment scores at Visit 2 (P < .0001). Adverse events were reported among 31 patients, mainly affecting the gastrointestinal system. Twenty-four patients (13.04%) reported 39 adverse events considered related to treatment. No significant change in physical exam was noted at Visit 2 in relation to Visit 1. CONCLUSIONS: These open label, historically controlled study results suggest the need for randomized, blinded, placebo and active substance controlled clinical trials. (Curr Ther Res Clin Exp. 2020; 81:XXX-XXX).
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BACKGROUND: Since 1985, the author has been using the single central block technique for breast reduction and mastopexy, prioritizing the good relation between the final breast shape and the length of the scars, different from other authors who emphasize only the shape of the breast (Peixoto in Plast Reconstr Surg 65(2):217-225, 1980; Aesthet Plast Surg 8:231-236, 1984) and others who have drawn attention to the length of the scars (Arié in Rev Latinoam Cir Plast 3:23-31, 1957; Bozola in Plast Reconstr Surg 85:728-738, 1990; Sepúlveda in Rev Bras Cir 71(1):11-18, 1981). In this study, the author describes the use of a single central block of the mammary tissue and the nipple-areolar complex (NAC), dissected from the skin flaps and based on the superior vascular pedicle for reduction mammoplasty and mastopexy (Erfon et al. in Annals of the international symposium recent advances in plastic surgery, São Paulo, 1989; Hinderer (ed) Plastic surgery, Elsevier, Madrid, 1992; Proceedings of the 65th annual scientific meeting of the American society of plastic and reconstructive surgeons, Dallas, 1996). METHODS: A retrospective study was performed, evaluating patients who underwent breast reduction and mastopexy using the single central block technique from July 1985 to December 2018 by a senior author. RESULTS: A total of 2097 procedures were performed using this technique, 1556 being reduction mammoplasties and 541 mastopexies. The mean patient age was 44, and the mean weight of tissue resected was 455 g. Fat necrosis on the distal area of the flap was observed in 47 cases (2.24%). Hematoma was observed in 6 patients (0.28%). Surgical revisions were undertaken in 75 patients (3.57%). Hypertrophic scars occurred in 12 of the cases (0.57%). Dehiscence in the inverted "T" scars occurred in 78 of the surgeries (3.71%). CONCLUSIONS: This technique allows the surgeon to easily form a good cone shape of the breast, repositioning the NAC and preserving its vascularization and sensation without tension on the skin flaps sutures, resulting in smaller and better scars. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
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Mamoplastia/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Mamilos/cirurgia , Estudos Retrospectivos , Retalhos Cirúrgicos , Fatores de Tempo , Adulto JovemRESUMO
Bacteria-synthesized polysaccharides have attracted interest for biomedical applications as promising biomaterials to be used as implants and scaffolds. The present study tested the hypothesis that cellulose exopolysaccharide (CEC) produced from sugarcane molasses of low cost and adequate purity would be suitable as a template for 2D and 3D neuron and/or astrocyte primary cultures, considering its low toxicity. CEC biocompatibility in these primary cultures was evaluated with respect to cell viability, adhesion, growth and cell function (calcium imaging). Polystyrene or Matrigel® matrix were used as comparative controls. We demonstrated that the properties of this CEC in the 2D or 3D configurations are suitable for differentiation of cortical astrocytes and neurons in single or mixed cultures. No toxicity was detected in neurons that showed NMDA-induced Ca2+ influx. Unlike other polysaccharides of bacterial synthesis, the CEC was efficient as a support even in the absence of surface conjugation with extracellular matrix proteins, maintaining physiological characteristics of cultured neural cells. These observations open up the perspective for development of a novel 3D biofunctional scaffold produced from bacterial cellulose and obtained from renewable sources whose residues are not pollutants. Its low cost and possibility to be manufactured in scale are also suitable for potential applications in regenerative medicine.
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Astrócitos/citologia , Neurônios/patologia , Polissacarídeos/química , Cultura Primária de Células , Saccharum/química , Animais , Materiais Biocompatíveis , Cálcio/química , Adesão Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Coloides/química , Matriz Extracelular/metabolismo , Feminino , Hidrogéis/química , Imageamento Tridimensional , Imuno-Histoquímica , Melaço , N-Metilaspartato/química , Neurônios/metabolismo , Ratos , Ratos Wistar , Estresse Mecânico , Engenharia Tecidual/métodosRESUMO
In this paper the on-the-field performance of a WDM-PON optical access providing quintuple-play services using orthogonal frequency division multiplexing (OFDM) modulation is evaluated in a real fiber-to-the-home (FTTH) network deployed by Towercom operator in Bratislava (Slovakia). A bundle of quintuple-play services comprising full-standard OFDM-based signals (LTE, WiMAX, UWB and DVB-T) and an ad-hoc OFDM-GbE signal is transmitted in coexistence per single user. Both downstream and upstream transmission performances are evaluated in different on-the-field long-reach optical link distance configurations. Four wavelength multi-user transmission of quintuple-play OFDM services is demonstrated exceeding 60.8 km reach in standard single mode fiber.
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The development of vaccinations has been game-changing in the ongoing effort to combat the COVID-19 pandemic. Until now, adverse effects are being reported at low frequency, including thrombocytopenia and myocarditis. Careful monitoring for any suspicious symptoms and signs following vaccination is necessary. We report a case of hemophagocytic lymphohistiocytosis (HLH) after mRNA COVID-19 vaccine in a 23-year-old female with ulcerative colitis. Diagnosis was made according to HLH-2004 criteria and the patient was treated with dexamethasone with response. Our report aimed to draw attention to the potential relation between COVID-19 vaccines and HLH and the necessity of continued surveillance, especially in at-risk populations such as those with underlying immune dysregulation.
O desenvolvimento de vacinas foi um ponto de viragem no combate contra a pandemia da COVID-19. Até ao momento, os efeitos adversos como a trombocitopenia e miocardite têm sido reportados com baixa frequência. A monitorização cuidadosa de qualquer sinal ou sintoma suspeitos é essencial. Reportamos um caso de linfohistiocitose hemofagocítica após vacinação contra a COVID-19 com uma vacina de mRNA, numa jovem de 23 anos com colite ulcerosa. O diagnóstico obedeceu os critérios HLH-2004 e a paciente foi tratada com dexametasona, com resposta. Pretendemos chamar à atenção para a potencial relação entre a vacinação para a COVID-19 e a HLH e a necessária contínua vigilância, especialmente em populações de maior risco, como as portadoras de doenças imuno-mediadas.
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Balanoposthitis can affect men in immunocompromised situations, such as HIV infection and diabetes. The main associated microorganism is Candida albicans, which can cause local lesions, such as the development of skin cracks associated with itching. As an alternative to conventional treatment, there is a growing interest in the photodynamic inactivation (PDI). It has been shown that the association of photosensitizers with metallic nanoparticles may improve the effectiveness of PDI via plasmonic effect. We have recently shown that the association of methylene blue (MB), a very known photosensitizer, with silver prismatic nanoplatelets (AgNPrs) improved PDI of a resistant strain of Staphylococcus aureus. To further investigate the experimental conditions involved in PDI improvement, in the present study, we studied the effect of MB concentration associated with AgNPrs exploring spectral analysis, zeta potential measurements, and biological assays, testing the conjugated system against C. albicans isolated from a resistant strain of balanoposthitis. The AgNPrs were synthesized through silver anisotropic seed growth induced by the anionic stabilizing agent poly(sodium 4-styrenesulfonate) and showed a plasmon band fully overlapping the MB absorption band. MB and AgNPrs were conjugated through electrostatic association and three different MB concentrations were tested in the nanosystems. Inactivation using red LED light (660 nm) showed a dose dependency in respect to the MB concentration in the conjugates. Using the highest MB concentration (100 µmolâ L-1) with AgNPr, it was possible to completely inactivate the microorganisms upon a 2 min irradiation exposure. Analyzing optical changes in the conjugates we suggest that these results indicate that AgNPrs are enhancers of MB photodynamic action probably by a combined mechanism of plasmonic effect and reduction of MB dimerization. Therefore, MBAgNPrs can be considered a suitable choice to be applied in PDI of resistant microorganisms.
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Candida albicans , Azul de Metileno , Fotoquimioterapia , Fármacos Fotossensibilizantes , Prata , Candida albicans/efeitos dos fármacos , Azul de Metileno/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fotoquimioterapia/métodos , Prata/farmacologia , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Balanite (Inflamação)/tratamento farmacológico , Balanite (Inflamação)/microbiologia , HumanosRESUMO
The burden of Inflammatory Bowel Disease (IBD) is increasing worldwide, with a particular increase in the prevalence in the elderly population, due to the ageing of young-onset IBD as well as to the increasing incidence in elderly patients. Elderly IBD patients present specific challenges to the treating physician, as they have comorbidities, lower functional reserves, and higher risk of treatment-related complications. The diagnosis of IBD in the elderly may be difficult due to a more subtle disease presentation and to a wide range of differential diagnosis. Moreover, as these patients are often excluded from clinical trials, there is a lack of high-quality evidence to inform on the most appropriate management. Despite an increasing prevalence, the management of IBD in the elderly is still hindered by frequent misconceptions by physicians treating these patients. Due to a erroneous notion of a milder disease course and fear of adverse events, elderly IBD-patients are managed with frequent and continuous use of steroids and undertreated with effective medical therapies. In this review, we describe the principles of management of IBD in the elderly, which is a topic of increasing importance to IBD clinics, that will have to progressively adapt to care for an ageing population.
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Colite Ulcerativa , Doenças Inflamatórias Intestinais , Idoso , Humanos , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Comorbidade , Esteroides/uso terapêutico , Diagnóstico Diferencial , Progressão da Doença , Colite Ulcerativa/epidemiologiaRESUMO
Teaching Point: Although inguinal hernias are very common, stomach entrapment within an inguinal hernia is rare.
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Undifferentiated osteoclast-like giant cell carcinomas (UOLGCCs) of the digestive tract are very rare, with only a few cases reported in the literature. An 82-year-old man was referred to the emergency department for melena. Endoscopic examination revealed a hemicircumferential ulcerovegetative lesion, involving the bulbar apex and extending to the second portion of the duodenum; biopsies revealed an UOLGCC. The patient underwent transfusion support therapy, and he was proposed for best supportive care. Duodenal UOLGCC is an extremely rare cause of upper gastrointestinal bleeding. Clinical findings and therapeutic approach represent a challenge in this pathology.
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Mycotoxins are toxic and carcinogenic metabolites produced by groups of filamentous fungi that colonize food crops. Aflatoxin B1 (AFB1), ochratoxin A (OTA) and fumonisin B1 (FB1) are among the most relevant agricultural mycotoxins, as they can induce various toxic processes in humans and animals. To detect AFB1, OTA and FB1 in the most varied matrices, chromatographic and immunological methods are primarily used; however, these techniques are time-consuming and expensive. In this study, we demonstrate that unitary alphatoxin nanopore can be used to detect and differentiate these mycotoxins in aqueous solution. The presence of AFB1, OTA or FB1 inside the nanopore induces reversible blockage of the ionic current flowing through the nanopore, with distinct characteristics of blockage that are unique to each of the three toxins. The process of discrimination is based on the residual current ratio calculation and analysis of the residence time of each mycotoxin inside the unitary nanopore. Using a single alphatoxin nanopore, the mycotoxins could be detected at the nanomolar level, indicating that alphatoxin nanopore is a promising molecular tool for discriminatory analysis of mycotoxins in aqueous solution.
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Aflatoxinas , Fumonisinas , Micotoxinas , Nanoporos , Ocratoxinas , Animais , Humanos , Ocratoxinas/análise , Fumonisinas/toxicidade , Aflatoxinas/análise , Micotoxinas/análise , Aflatoxina B1/análiseRESUMO
Spotted fever rickettsiosis is a zoonosis transmitted by ticks, having a varied clinical course that can lead to death if not managed properly. In Brazil it is more commonly observed in the Southeast, being an emerging public health problem. Hazard mapping models are common in different areas of knowledge, including public health, as a way of inferring reality and seeking to reduce or prevent damage. The aim of this study is to offer a spatial heuristic methodology for assessing the potential risk of transmission of spotted fever in the Rio de Janeiro state, located in the southeastern region of Brazil. For this, we used geospatial tools associated with eco-epidemiological data related to the clinical profile of the disease. The results achieved were substantially encouraging, considering that there are territories with greater or lesser expectation of risk for spotted fever in the study area. We observed that there are important distinctions between the two rickettsiosis scenarios in the same geographic space and that the areas where there is a greater potential risk of contracting rickettsiosis coincide with the administrative regions that concentrated the cases of hospitalization and deaths from the disease, concluding that the scenery found are relevant to the case series for the disease and that the planning of surveillance actions can gain in quality if the use of this spatial analysis tool is incorporated into the routine of local health management.
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Infecções por Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Carrapatos , Animais , Brasil/epidemiologia , Saúde Pública , Rickettsiose do Grupo da Febre Maculosa/epidemiologiaRESUMO
Despite extensive research in the nanopore-sensing field, there is a paucity of experimental studies that investigate specific ion effects in confined spaces, such as in nanopores. Here, the effect of halogen anions on a simple bimolecular complexation reaction between monodisperse poly(ethylene glycol) (PEG) and α-hemolysin nanoscale pores have been investigated at the single-molecule level. The anions track the Hofmeister ranking according to their influence upon the on-rate constant. An inverse relationship was demonstrated for the off-rate and the solubility of PEG. The difference among anions spans several hundredfold. Halogen anions play a very significant role in the interaction of PEG with nanopores although, unlike K(+), they do not bind to PEG. The specific effect appears dominated by a hydration-dehydration process where ions and PEG compete for water. Our findings provide what we believe to be novel insights into physicochemical mechanisms involved in single-molecule interactions with nanopores and are clearly relevant to more complicated chemical and biological processes involving a transient association of two or more molecules (e.g., reception, signal transduction, enzyme catalysis). It is anticipated that these findings will advance the development of devices with nanopore-based sensors for chemical and biological applications.
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Biofísica/métodos , Halogênios/química , Modelos Químicos , Ânions , Toxinas Bacterianas/metabolismo , Condutividade Elétrica , Eletro-Osmose , Proteínas Hemolisinas/metabolismo , Cinética , Limite de Detecção , Polietilenoglicóis/química , Solubilidade , Soluções , Água/químicaRESUMO
MicroRNA-9 (miR-9) modulates gene expression and demonstrates high structural conservation and wide expression in the central nervous system. Bioinformatics analysis predicts almost 100 ion channels, membrane transporters and receptors, including genes linked to primary familial brain calcification (PFBC), as possible miR-9-5p targets. PFBC is a neurodegenerative disorder, characterized by bilateral and symmetrical calcifications in the brain, associated with motor and behavioral disturbances. In this work, we seek to study the influence of miR-9-5p in regulating genes involved in PFBC, in an osteogenic differentiation model with SaOs-2 cells. During the induced calcification process, solute carrier family 20 member 2 (SLC20A2) and platelet-derived growth factor receptor beta (PDGFRB) were downregulated, while platelet-derived growth factor beta (PDGFB) showed no significant changes. Significantly decreased levels of SLC20A2 and PDGFRB were caused by the presence of miR-9-5p, while PDGFB showed no regulation. We confirmed the findings using an miR-9-5p inhibitor and also probed the cells in electrophysiological analysis to assess whether such microRNA might affect a broader range of ion channels, membrane transporters and receptors. Our electrophysiological data show that an increase of the miR-9-5p in SaOs-2 cells decreased the density and amplitude of the output ionic currents, indicating that it may influence the activity, and perhaps the expression, of some ionic channels. Additional investigations should determine whether such an effect is specific to miR-9-5p, and whether it could be used, together with the miR-9-5p inhibitor, as a therapeutic or diagnostic tool.
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Encefalopatias/metabolismo , Calcinose/metabolismo , Diferenciação Celular , MicroRNAs/metabolismo , Osteoblastos/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo , Potenciais de Ação , Encefalopatias/genética , Calcinose/genética , Linhagem Celular Tumoral , Humanos , MicroRNAs/genética , Osteoblastos/citologia , Osteoblastos/fisiologia , Proteínas Proto-Oncogênicas c-sis/genética , Proteínas Proto-Oncogênicas c-sis/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genéticaRESUMO
Mastitis is a bacterial infection that affects all lactating mammals, and in dairy cattle, it leads to a reduction in their milk production and, in worse cases, it may lead to animal death. One viable therapeutic modality for overcoming bacterial resistance can be photodynamic inactivation (PDI), a therapeutic modality for bacterial infection treatment. One of the main factors that can lead to an efficient PDI process is the association of metallic nanoparticles in the close vicinity of photosensitizers, which has shown promising results due to localized surface plasmon resonance phenomena. In this work, methylene blue (MB) molecules were associated with Ag prismatic nanoplatelets (AgNPrs) to use as PDI photosensitizer against Staphylococcus aureus isolated from bubaline mastitis. The optical plasmonic activity of AgNPrs was tuned to the MB absorption region (600-700 nm) by inducing their growth into prismatic shapes by a seed-mediated procedure, using poly (sodium 4-styrene sulfonate) as the surfactant. A simulation on the plasmonic properties of the nanoprisms, applying particle size within the dimensions determined by TEM image analysis (d = 32 ± 6 nm), showed a 30 % increase of the incident field on the prismatic tips. Photodynamic results showed that the electrostatic AgNPr-MB conjugates promoted enhancement (ca. 15 %) of the reactive oxygen species production. Besides, PDI mediated by AgNPrs-MB led to the complete inactivation of the mastitis S. aureus strain after 6 min inactivation, in contrast to PDI mediated by MB, which reduced less than a 0.5 bacterial log. Thus, the results show this plasmonic enhanced photodynamic tool's potential to be applied in the inactivation of multi-resistant bacterial strains.
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Mastite , Fotoquimioterapia , Animais , Bovinos , Feminino , Humanos , Lactação , Mastite/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Prata/farmacologia , Staphylococcus aureusRESUMO
Introduction: Since photobiomodulation therapy (PBMT) favors in vitro mesenchymal stem cell (MSC) preconditioning before MSC transplantation, increasing the proliferation of these cells without molecular injuries by conserving their characteristics, in the present in vitro study we analyzed the effect of PBMT on the proliferation and osteogenic differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs). Methods: Irradiation with an InGaAIP Laser (660 nm, 10 mW, 2.5 J/cm2 , 0.08 cm2 spot size, and 10 s) was carried out. The cells were divided into four groups: CONTROL [cells grown in Dulbecco's Modified Eagle Medium (DMEM)], OSTEO (cells grown in an osteogenic medium); PBMT (cells grown in DMEM+PBMT), and OSTEO+PBMT (cells grown in an osteogenic medium plus PBMT). The cell proliferation curve was obtained over periods of 24, 48 and 72 hours using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Osteogenic differentiation was analyzed by the formation of calcium nodules over periods of 7, 14 and 21 days. Morphometric analysis was performed to quantify the total area of nodular calcification. Results: The highest cell proliferation and cell differentiation occurred in the OSTEO+PBMT group, followed by the PBMT, OSTEO and CONTROL groups respectively, at the observed times (P <0.05). Conclusion: PBMT enhanced the osteogenic proliferation and the differentiation of hUCMSCs during the periods tested, without causing damage to the cells and preserving their specific characteristics, a fact that may represent an innovative pretreatment in the application of stem cells.